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This article is an electronic publication in Spectrochimica Acta Electronica (SAE), the electronic section of Spectrochimica Acta Part B (SAB). Accompanying this hard copy text is a disk containing the program, source flies, data files and a brief manual along with a few programming notes. The main article discusses the purpose of this work, and the Appendix provides brief instruction on the use of the program, manipulation of the data, and source code. An automatic file selection system for the control of a rapid scanning spectrometer performing atomic emission spectrometry has been developed using the PROLOG language. The system can be “taught” the elemental composition of a given sample type. It uses this information (when available) to generate a linear search strategy which minimizes the number of lines that need to be measured. The rules used by the system can be observed during system operation to allow a trace of the logic. Reading of the initial data base takes no more than 6 s and then decisions are made in less than 1 s per line.  相似文献   
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Russian Journal of General Chemistry - Kinetics of the reaction of triphenylphosphine with methyl vinyl ketone has been studied using the stopped flow technique. The experimental data have...  相似文献   
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The dissociative adsorption of N2 on W(1 1 0) is studied using classical dynamics on a six-dimensional potential energy surface obtained from density functional theory calculations. Two distinct channels are identified in the dissociation process: a direct one and an indirect one. It is shown that the direct channel is inhibited for low energy molecules (Ei < 400 meV) and low incidence angles. The indirect channel includes long-lasting dynamic trapping of the molecule at the surface before dissociation. The dependence of the sticking coefficient on the initial incidence angle is analyzed. The theoretical results compare well with values measured using molecular beam techniques.  相似文献   
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It is very interesting to measure the bistatic characteristics of sound scattering by the ocean bottom and surface for the development of present-day hydrolocation net-centric schemes. Possible methods for measuring scattering bistatic characteristics are evaluated. The angular characteristics of reverberation related to illumination of a water area by active linearly frequency-modulated signals are studied using linear passive arrays to test a measuring scheme in a shallow water area with a depth of ~20 m in the 1–3 kHz frequency range. The bistatic sound-scattering characteristics in the water area are calculated based on the measurements. The obtained characteristics are compared with the known data on the backscattering of sound.  相似文献   
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We study miscible fluid displacement in heterogeneous porousmedia, in the presence of gravity, where the heterogeneity consists of multiple layers. Miscible fluids of different density and viscosity contrasts are used, such that the displacementis hydrodynamically stable. Depending on the values of the control parameters, the overall fluid displacement exhibits either an enhancement of the effect of heterogeneity or a damping. For a sufficiently large viscosity and/or density contrast, the effectof heterogeneity is overcome and the multi-layer system behaves as a single homogeneous layer. We determine experimentally an associated phasediagram and compare our data to a theoretical model valid for systemsof large aspect ratio.https://doi.org/10.1209/epl/i1996-00194-y  相似文献   
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Sing RL  Salin ED 《Talanta》1984,31(8):565-571
An inexpensive but powerful computer network particularly suited to the research laboratory is discussed. The primary advantages of the system are low cost, flexibility, freedom of choice of manufacturer, and convenience of upgrading. The principal limitations are speed of data transfer and the requirement for a certain level of skill during setting up. The system operates with both the CP/M and MP/M operating systems, but the principles of operation are generally applicable.  相似文献   
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We discuss the non-relativistic theory of electron capture from atoms (or ions) by ions when the relative velocity of the collision is greater than the orbital velocity of the captured electron. We emphasize the specific difficulties due to the two-body Coulomb potentials occurring in this process We show how the simplifications introduced by the small value of the electron to proton mass ratio can be used to provide a valuable tool to evaluate the adequacy of the existing theories. Extensive comparisons between theory and experiment are carried out and a number of new theoretical results are presented.  相似文献   
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